When installing electrical wiring in buildings, electrical cables and wires are commonly routed through metal pipe or conduit. The pipe and conduit are commonly cut to the correct size in order to fit the various runs between junction boxes, outlets, switches and other electrical devices. The cut edges of the pipe and conduit however present a hazard to the cables or wires at their entrances as vibration or temperature caused expansion and contraction can lead to abrasion of the cable sheaths. Manufacturers supply ring-shaped bushings for covering the cut edges of pipes and conduit, however, the ring-shaped bushings must be installed before cable is routed through the pipe or conduit. After cables have been run through the pipes and conduit, a ring-shaped bushing cannot be installed over the cut edges without removing the existing cables, which is impractical and time-consuming. Frequently, in order to accommodate addition of new cables within existing conduit, installers will cut the ring-shaped bushings in half and reinstall the resultant split bushings them on the conduit edges, however the reinstalled split bushing fits loosely on the pipe or conduit and typically does not span the entire periphery of the conduit edge. In order to be qualified for use on electrical conduit, bushings must pass a test specified by Underwriters Lab (UL). UL requires that the bushing remain tightly secured to the conduit while cables are pulled there through. Full ring bushings that have been split by the installers, as a result of the loose fit, typically fail to pass the UL test.
Therefore, what is needed is a device and method for preventing abrasion of electrical cables by the edges of pipe and conduit. The protective device should be capable of being installed on the edges of pipe and conduit after initial installation of the electrical cables therein, and should be capable of passing the UL test. The device should provide a non-abrasive surface for protecting installed electrical cables and wires from direct contact with the cut edges of pipes or conduit, should cover the entirety of the periphery of the conduit edge to which it is attached, and must be capable of being secured tightly to the pipe or conduit in order to meet the UL requirements.